refund

hi please assist me i have a problem with absa i have a loan with them which i am paying have the arrangement with them to pay certain amount which i am paying December they just took R12 000 in my account without informing or communicating with me after calling them more than 6 times they only send back to me the half of that amount and when i asked them why there was no respond then i made the new arrangement to increase the instalment to the one they said i have to pay but today again they just took R4300 without any communication while i called them January and we made the arrangement so i can't deal with this nonsense now and i need the full refund because i have to pay my kids school fees this so irritating now